Virtual algorithm is a new image processing measure. With regard to a particular sub-pixel arrangement, virtual algorithm can improve a lower physical resolution to a higher virtual resolution, optimize display effect, and enhance visual experience of human eyes.
Virtual algorithm usually adopts filters to process input signals, the input signals are re-sampled by the filters for allocation, thus realizing virtual display. But the filters in virtual algorithm can not accurately process different types of image, for example, color edge may appear in some filters in a case of a slant pattern, this phenomenon is typically called as color aliasing. In order to reduce color aliasing effect, on one hand, it needs to constantly test and feed back, optimize the filters, thus improving display effect; on the other hand, it needs to adopt different filters to process a different type of image or a different location on the same image. For example, usually, a universal filter is adopted for a location having no boundary, and a boundary filter is adopted for a location having a boundary.
To implement filtering in different situations, it needs to process luminance signals of input data, design discriminating process, identify sharp boundaries therein, classify specific horizontal line, vertical line, left diagonal line, and right diagonal line, thereby adopting different filters.
Therefore, how to effectively discriminate a boundary of an image is a technical problem that needs to be immediately solved by those skilled in the art.